Sensors And Micro-Controllers
SCHOOLS OF ROBOTICS
• Mechanical Design
• Electronics
• Programming
.
AUTONOMOUS ROBOT
WHAT ARE SENSORS ?
• Any device that converts a change in physical quantity into electrical signals.
TSOP 1738
• It is a Digital IR Sensor.
• Works for IR pulse rate 38 KHz.
• Pulse rate set by microcontroller.
• Accurately distinguish between two colors.
• Outputs – 0 and 5 Volts.
CIRCUIT DIAGRAM
TSOP RANGE INCREASE CIRCUIT
ANALOG IR SENSOR
• Measures amount of reflected IR light
• Outputs in the range of 0V to 5V
• Hence, called Analog Sensor
CIRCUIT DIAGRAM
LIGHT DEPENDENT RESISTOR
• Made of calcium Sulphate
• Act like open circuit in absence of light
• In light, resistance drops from
1 M ohms to10 ohms
• Popularly called LDRs.
7805
• Microcontrollers – 5V
• Motors – 12V
• Converts 8V to 12V into 5V
• Rest lost as heat
• Current Rating - 0.5 A
INTEGRATED CIRCUITS
• Programmable – Simplest form of microcontroller
• Non – Programmable
• E.g. 555, AND gate, OR gate, Mux, Inverters, etc.
MICRO-CONTROLLERS
• A micro controller is the brain of the robot.
• Logic tables relating Input and Output can be defined by you.
• Many other useful features built into the IC itself.
CONFUSED ?
WORKING
• Consists of CPU interfaced with RAM and Flash Memory.
• Flash memory is Programmable
• CPU accesses information from RAM, which gets it from the flash memory
ATMEGA 16
ATMEGA 8
PROGRAMMING
• Understands only binary language
• Code written in C
• Used to generate a .hex file
• Transfer the .hex file using a programmer
I/O PINS
• DDRX Registers
• PORTX Registers
• PINX Registers
TIMERS
• Timer 0 – 8 bit ( OC0 at PB3)
• Timer 1 – 16 bit ( 2 parts, OC1A at PD5 and OC1B at PD4)
• Timer 2, 8 bit (OC2 at PD7)
• System Clock (fs)
• Timer Clock
THANK YOU